I'm playing with some example code from Mac OS X Internals, and I'm getting: 2010-08-25 12:06:53 PM com.apple.launchd[497] (0x10f7c0.simple_ipc_serve[1322]) bootstrap_create_service() is only allowed against legacy Mach jobs: com.osxbook.FactorialServer I took a quick look through the sources and it appears the only way to get a "legacy" job is to have job_new_via_mach_init called in launchd_core_logic.c.... interestingly nothing seems to call it. Is there anyway to get this running on 10.5 the way that Amit originally coded it, or does bootstrap_create_service just not work anymore? This is purely for learning... not shipping this. (Note this is 10.5 I'm running on right now). Cheers, Dave